Author(s)

Komlavi Yayehd^1*, Tchaa Tcherou², Hervé Libérus A. Edorh¹, Agossou Defodji¹, Mohamed Kpelafia¹, Ekpé Togbossi¹, Ablawa Adzodo¹, Soulemane Pessinaba¹, Machihude Pio², Soodogoua Baragou¹, Findibe Damorou¹

¹Department of Cardiology, Faculty of Health Sciences, University of Lomé, Lomé, Togo.
²Department of Cardiology, Faculty of Health Sciences, University of Kara, Kara, Togo.

Introduction: Despite the rise of direct oral anticoagulants (DOACs), vitamin K antagonists (VKA) remain the most widely used oral anticoagulants in developing countries. The aim of this study was to estimate the prevalence of good anticoagulation in patients treated with VKA in Lomé and describe associated factors. Methods: This was a cross-sectional study conducted from November 2019 to October 2020 in the cardiology departments of two University teaching hospitals in Lomé (CHU Sylvanus Olympio and CHU Campus), involving patients on VKA for ≥3 months, with a target international normalized ratio (INR) of 2.5 and a therapeutic margin between 2 and 3. The quality of anticoagulation was assessed by the time in therapeutic range (TTR) which was assessed by the Rosendaal method. Good anticoagulation was defined by a TTR > 70%. Results: A total of 344 patients were included (mean age = 58 ± 13.8 years, women = 56.1%). Indications for VKA treatment were represented by venous thromboembolic disease (43.3%), supraventricular arrhythmia (28.2%), severe left ventricular systolic dysfunction (19.8%) and pulmonary hypertension (8.7%). The average TTR was 47.6 ± 20.8%. The rate of good anticoagulation was 17.7%. Factors associated with good anticoagulation were the use of fluindione vs acenocoumarol (OR = 11.17; 95% CI: 3.2 - 39.6; p = 0.0002), concomitant low-dose aspirin (OR 4.44; 95% CI: 1.4 - 13.9; p = 0.01) and INR monitoring exclusively by the patient himself (OR = 4.92; 95% CI: 1.5 - 16.3; p = 0.008). The rate of thromboembolic and hemorrhagic complications was each 2.6% and was not correlated with the quality of anticoagulation. Quality of anticoagulation by VKAs was poor in our practice. Factors associated with good anticoagulation were the use of fluindione vs acenocoumarol, concomitant low-dose aspirin and monitoring of INR exclusively by the patient himself. Conclusion: The quality of oral anticoagulation by VKAs could be improved in our practice by the creation of anticoagulation clinics for better therapeutic education of patients and efficient management of VKA dose, and the use of prescription assistance software.

Vitamin K Antagonists, Time in Therapeutic Range, Lomé, Togo

Yayehd, K. , Tcherou, T. , Edorh, H. , Defodji, A. , Kpelafia, M. , Togbossi, E. , Adzodo, A. , Pessinaba, S. , Pio, M. , Baragou, S. and Damorou, F. (2024) Assessment of Oral Anticoagulation with Vitamin K Antagonists in Patients Living in a Low-Income Country of West Africa. World Journal of Cardiovascular Diseases, 14, 27-42. doi: 10.4236/wjcd.2024.141004.